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In a meeting $60 \%$ of the members favour and $40 \%$ oppose a certain proposal. A member is selected at random and we take $\mathrm{X}=0$ if the opposed and $\mathrm{X}=1$ if he is in favour, then Var $\mathrm{X}=$
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2545 Upvotes
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The correct answer is:
0.24
$$
\text { From the given data, we write }
$$

$$
\text { Variance }=\Sigma \mathrm{p}_{\mathrm{i}} \mathrm{x}_{\mathrm{i}}^2-\left(\sum \mathrm{p}_{\mathrm{i}} \mathrm{x}_{\mathrm{i}}\right)^2=0.6-(0.6)^2=0.6-0.36=0.24
$$
\text { From the given data, we write }
$$

$$
\text { Variance }=\Sigma \mathrm{p}_{\mathrm{i}} \mathrm{x}_{\mathrm{i}}^2-\left(\sum \mathrm{p}_{\mathrm{i}} \mathrm{x}_{\mathrm{i}}\right)^2=0.6-(0.6)^2=0.6-0.36=0.24
$$
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